JPH10152522A - Apparatus for recovering unreacted monomer in vinyl chloride polymerization facility and recovery therefor - Google Patents
Apparatus for recovering unreacted monomer in vinyl chloride polymerization facility and recovery thereforInfo
- Publication number
- JPH10152522A JPH10152522A JP27651697A JP27651697A JPH10152522A JP H10152522 A JPH10152522 A JP H10152522A JP 27651697 A JP27651697 A JP 27651697A JP 27651697 A JP27651697 A JP 27651697A JP H10152522 A JPH10152522 A JP H10152522A
- Authority
- JP
- Japan
- Prior art keywords
- tank
- vinyl chloride
- monomer
- pressure
- polymerization
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、重合反応槽を用い
て塩化ビニル系重合体を製造したのち、重合反応後の塩
化ビニル系重合体と未反応単量体とを含む内容物を該反
応槽から抜き出しながら、同時に該内容物から前記未反
応単量体を回収する方法に関する。BACKGROUND OF THE INVENTION The present invention relates to a method for producing a vinyl chloride polymer using a polymerization reaction tank, and then subjecting the content containing the vinyl chloride polymer after polymerization to unreacted monomers to the reaction. The present invention relates to a method for simultaneously recovering the unreacted monomer from the contents while extracting the unreacted monomer from the tank.
【０００２】[0002]
【従来の技術】塩化ビニル系重合体の工業的な製造方法
としては、水性懸濁重合、塊状重合、乳化重合等が行わ
れているが、水性懸濁重合及び水を分散媒とする乳化重
合が、最も広く行われている（これらをあわせて水性重
合という）。また上記塩化ビニル系重合体としては、塩
化ビニル単独重合体の他、塩化ビニル単量体と共重合可
能な単量体との共重合体、例えば塩化ビニル・酢酸ビニ
ル共重合体、塩化ビニル・オレフィン系重合体、更に塩
化ビニルのグラフト重合体、例えばエチレン・酢酸ビニ
ル共重合体にグラフト重合したもの等が知られている。
2. Description of the Related Art As an industrial production method of a vinyl chloride polymer, aqueous suspension polymerization, bulk polymerization, emulsion polymerization and the like are performed. Aqueous suspension polymerization and emulsion polymerization using water as a dispersion medium are known. Is the most widely used (these are collectively referred to as aqueous polymerization). Examples of the vinyl chloride polymer include, in addition to a vinyl chloride homopolymer, a copolymer of a vinyl chloride monomer and a copolymerizable monomer, for example, a vinyl chloride / vinyl acetate copolymer, a vinyl chloride / vinyl acetate copolymer. Olefin polymers, and further, graft polymers of vinyl chloride, for example, those obtained by graft polymerization to an ethylene / vinyl acetate copolymer, and the like are known.
【０００３】従来、塩化ビニル系重合体の製造方法にお
いては、重合反応槽に仕込まれた塩化ビニル系単量体の
うちの７０〜９５％が重合すると、以降の反応が極めて
遅くなるために、この段階で反応を停止させて、該重合
反応槽中において、その頂部に接続された配管から未反
応単量体のみを或る程度充分に回収した後に、生成した
塩化ビニル系重合体と未反応単量体とを含む内容物を該
反応槽から回収していた。しかし、反応槽中において予
め未反応単量体を充分に回収しておく方法は、その作業
に時間を要する。塩化ビニル系重合体の製造方法は、一
般的にバッチ方式で行われているため、重合反応槽が塞
がっている時間は次のバッチの重合を行えない。従っ
て、重合反応自体が短時間で終了しても、その後の回収
処理に多くの時間を費やすことは、塩化ビニル重合体製
品の生産量の低下につながる。この回収作業に要する時
間を短縮する目的から、重合反応後の反応槽中で未反応
単量体を回収する作業を充分に行わずに、重合反応槽内
が充分高圧を保った状態、すなわち高濃度の未反応単量
体を依然含んだままの状態で、一気に別のタンクに抜き
出す方法も考えられている。しかし、この方法だと、抜
き出された内容物中に含まれている未反応塩化ビニル系
単量体そのものの濃度が高いため、この内容物中での未
反応塩化ビニル系単量体の濃度のバラツキの高低差が大
きくなって、引き続き行われる脱塩化ビニル系単量体工
程での運転が不安定になるという支障をきたすほか、従
来の回収設備では、内容物に含まれる未反応塩化ビニル
系単量体の量が増えれば、それだけ回収された内容物を
貯留または通過させる際のタンクに高い耐圧性を要求さ
れ、高圧設計に伴う費用が高額化し、建設コストの高騰
を余儀なくされていた。Conventionally, in a method for producing a vinyl chloride polymer, if 70 to 95% of the vinyl chloride monomer charged in a polymerization reactor is polymerized, the subsequent reaction becomes extremely slow. At this stage, the reaction is stopped, and in the polymerization reaction tank, only a certain amount of the unreacted monomer is sufficiently recovered from the pipe connected to the top of the polymerization reaction tank. The content containing the monomer was recovered from the reaction vessel. However, the method of sufficiently recovering the unreacted monomer in advance in the reaction tank requires time for the operation. Since the method for producing a vinyl chloride polymer is generally performed in a batch system, the polymerization of the next batch cannot be performed while the polymerization reaction tank is closed. Therefore, even if the polymerization reaction itself is completed in a short time, spending much time in the subsequent recovery treatment leads to a decrease in the production amount of the vinyl chloride polymer product. For the purpose of shortening the time required for this recovery operation, the operation of recovering unreacted monomers in the reaction tank after the polymerization reaction is not sufficiently performed, and the state in which the pressure in the polymerization reaction tank is sufficiently high, that is, A method has been considered in which the unreacted monomer is still contained at a certain concentration, and is immediately discharged to another tank. However, according to this method, the concentration of the unreacted vinyl chloride-based monomer itself contained in the extracted contents is high, so that the concentration of the unreacted vinyl chloride-based monomer in the extracted contents is high. In addition to the fact that the difference in the height of the dispersion increases, the operation in the subsequent vinyl chloride-based monomer process becomes unstable, and in the conventional recovery equipment, unreacted vinyl chloride contained in the contents As the amount of the system monomer increases, the tank used to store or pass the recovered content must have high pressure resistance, and the cost associated with the high-pressure design increases, resulting in an increase in construction costs. .
【０００４】[0004]
【発明が解決しようとする課題】本発明の目的は、未反
応単量体を反応槽内で実質的に充分に回収することなし
に、あるいは、全く回収せずに、安価な低圧設計のブロ
ーダウンタンクに塩化ビニル系重合体と高濃度の未反応
単量体を回収することを可能ならしめることにより、塩
化ビニル系重合体の生産効率を含む総合的な生産コスト
を向上させることである。SUMMARY OF THE INVENTION It is an object of the present invention to provide an inexpensive low-pressure blower without substantially or completely not recovering unreacted monomers in a reaction vessel. An object of the present invention is to improve the overall production cost including the production efficiency of a vinyl chloride polymer by making it possible to collect a vinyl chloride polymer and a high concentration of unreacted monomer in a down tank.
【０００５】[0005]
【課題を解決するための手段】本発明者らは上記課題を
解決すべく鋭意検討した結果、移送管とブローダウンタ
ンクに独特な構造と計装を工夫することにより、ブロー
ダウンタンクの低圧設計を可能にし、塩化ビニル系重合
体の生産効率を向上させることができることを見いだし
本発明を完成するに至った。すなわち、本発明は、下記
の態様を有する。 （１）（ａ）塩化ビニル単量体、または塩化ビニルとこ
れと共重合可能な単量体との混合物を重合して塩化ビニ
ル系重合体を製造するための重合反応槽と、（ｂ）該反
応槽から重合反応後の塩化ビニル系重合体と未反応単量
体を含む内容物を移送するための移送管と、（ｃ）該移
送管を経て移送される前記内容物を一時的に貯留または
通過させるためのタンクであって、その内容積が前記重
合反応槽の内容積の１〜３倍であり、耐圧許容圧力が１
ｋｇ／ｃｍ2Ｇ以下であるブローダウンタンクと、
（ｄ）該ブローダウンタンク出口に設けられた通気管
と、（ｅ）前記ブローダウンタンク内の圧力が前記耐圧
許容圧力以下になるようにブローダウンタンク入り口の
移送管内の流量を調整する圧力調整手段と、（ｆ）該通
気管を経て移動してくる未反応単量体を含むガスを保留
するためのガスホルダーとを有し、前記通気管の内径が
前記移送管の内径より大きいことを特徴とする、塩化ビ
ニル重合設備における未反応単量体の回収装置。 （２）前記通気管の内径が前記移送管の内径の１．５〜
４倍である前記（１）記載の回収装置 （３）ブローダウンタンクの側面内周が円形であり、重
合反応槽から該ブローダウンタンクへ接続する移送管
が、該ブローダウンタンクの側面内周に対してその接線
方向に沿うように接続されていることを特徴とする前記
（１）または（２）記載の回収装置。 （４）塩化ビニル単量体、または塩化ビニル単量体とこ
れと共重合可能な単量体との混合物を反応槽に仕込んで
該単量体の８０重量％以上を重合させた後、未反応単量
体の内５０重量％以上が残存している状態で該残存する
未反応単量体と塩化ビニル系重合体を含む反応槽の内容
物をブローダウンタンクへ回収し、該ブローダウンタン
ク内の圧力を１ｋｇ／ｃｍ2Ｇ以下に保ちつつ、該ブロ
ーダウンタンクから前記未反応単量体を含むガスをガス
ホルダーへ回収することを特徴とする、塩化ビニル重合
設備における未反応単量体の回収方法。 （５）未反応単量体の内９０重量％以上が残存している
状態で、該残存する未反応単量体と塩化ビニル系重合体
を含む内容物をブローダウンタンクへ回収することを特
徴とする前記（４）記載の回収方法。 （６）重合反応槽の内圧が３ｋｇ／ｃｍ2Ｇ以上のとき
に、該反応槽の内容物を前記ブローダウンタンクへ回収
することを特徴とする前記（４）記載の回収方法。 （７）重合反応槽の内圧が５ｋｇ／ｃｍ2Ｇ以上のとき
に、該反応槽中の内容物をブローダウンタンクへ回収す
ることを特徴とする前記（４）記載の回収方法。Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors devised a unique structure and instrumentation for the transfer pipe and the blow-down tank to reduce the low-pressure design of the blow-down tank. And found that the production efficiency of the vinyl chloride polymer can be improved, and the present invention has been completed. That is, the present invention has the following aspects. (1) (a) a polymerization reaction tank for producing a vinyl chloride polymer by polymerizing a vinyl chloride monomer or a mixture of vinyl chloride and a monomer copolymerizable therewith; (b) A transfer pipe for transferring the contents containing the vinyl chloride polymer and the unreacted monomer after the polymerization reaction from the reaction tank; and (c) temporarily transferring the contents transferred through the transfer pipe. A tank for storing or passing, wherein the internal volume is 1 to 3 times the internal volume of the polymerization reaction tank, and the allowable pressure resistance is 1
a blowdown tank that is not more than kg / cm 2 G;
(D) a vent pipe provided at the outlet of the blowdown tank; and (e) pressure adjustment for adjusting the flow rate in the transfer pipe at the inlet of the blowdown tank so that the pressure in the blowdown tank is equal to or less than the allowable pressure resistance. Means; and (f) a gas holder for retaining gas containing unreacted monomer moving through the vent pipe, wherein the inner diameter of the vent pipe is larger than the inner diameter of the transfer pipe. Characteristic device for recovering unreacted monomers in vinyl chloride polymerization equipment. (2) The inner diameter of the ventilation pipe is 1.5 to less than the inner diameter of the transfer pipe.
(3) The inner periphery of the blow-down tank is circular, and the transfer pipe connecting from the polymerization reaction tank to the blow-down tank is the inner periphery of the blow-down tank. The collection device according to (1) or (2), wherein the collection device is connected to the tangential direction. (4) After charging a vinyl chloride monomer or a mixture of a vinyl chloride monomer and a monomer copolymerizable with the vinyl chloride monomer into a reaction vessel to polymerize 80% by weight or more of the monomer, In a state where 50% by weight or more of the reactive monomer remains, the contents of the reaction vessel containing the remaining unreacted monomer and vinyl chloride polymer are collected in a blowdown tank, and the blowdown tank is used. Recovering a gas containing the unreacted monomer from the blowdown tank to a gas holder while maintaining the internal pressure at 1 kg / cm 2 G or less, wherein the unreacted monomer in a vinyl chloride polymerization facility is Collection method. (5) In a state where 90% by weight or more of the unreacted monomer remains, the content containing the remaining unreacted monomer and the vinyl chloride polymer is collected into a blowdown tank. The recovery method according to the above (4). (6) The method according to (4), wherein when the internal pressure of the polymerization reaction tank is 3 kg / cm 2 G or more, the contents of the reaction tank are collected in the blowdown tank. (7) The method according to (4), wherein when the internal pressure of the polymerization reaction tank is 5 kg / cm 2 G or more, the contents in the reaction tank are collected into a blowdown tank.
【０００６】本発明の回収設備の例を図１と図２に示
し、本発明の回収方法を具体的に説明するが、本発明は
これによって限定されるものではない。本発明装置は、
塩化ビニル単量体、または塩化ビニル単量体とこれと共
重合可能な単量体との混合物を重合して塩化ビニル重合
体を製造するための重合反応槽１と、該反応槽１から内
容物を移送するための移送管２と、該移送管２を経て移
送される内容物を一時的に貯留または通過させるための
耐圧許容圧力が１ｋｇ／ｃｍ2Ｇ以下のブローダウンタ
ンク３と、該ブローダウンタンク３出口に設けられた通
気管４と、該ブローダウンタンク３内の圧力を検出する
圧力計７と、該圧力計７で検出された圧力が前記ブロー
ダウンタンクの耐圧許容圧力以下になるようにブローダ
ウンタンク３入口の移送管２内の流量を調整する圧力調
整弁６と、該通気管４を経て移動してくるガス状の未反
応単量体を保留するためのガスホルダー５とを有する。
尚、８は通気管４の途中に設けられたシールポットであ
る。このシールポットは、通気管４に溜まった水を抜く
作用と、ガス圧が異常に上昇した場合のガス抜きの作用
をする。ブローダウンタンク３の底部には、ブローダウ
ンタンク内の内容物から塩化ビニル系重合体、及び水等
の液状物質を本格的な塩化ビニルモノマーの除去を行う
装置へ移送するための配管９が接続され、バルブ１０が
設置されている。本発明で使用する重合反応槽１は、通
常の塩化ビニル系重合体の重合に使用するものであれば
よい。また、本発明で使用する移送管２も通常の塩化ビ
ニル系重合体の製造に使用されるものでよい。本発明の
回収設備において使用するブローダウンタンク３の耐圧
許容圧力は１ｋｇ／ｃｍ2Ｇ以下である。また、その容
量は、重合反応槽の容量の１〜３倍、好ましくは、１．
５〜２．５倍である。高圧設計のタンクを必要としない
ことから、設備費が安価で済む。本発明では、ブローダ
ウンタンク３とガスホルダー５を連結する通気管４は、
移送管２より充分大きな管径を有することが好ましく、
移送管２の内径の１．５〜４倍、好ましくは２〜３倍、
寸法的には２００〜５００ｍｍ、好ましくは２５０〜４
００ｍｍである。更に、該通気管の長さは短いほうが良
く、好ましくは１５０ｍ以下である。重合反応槽１内
で、予め、充分に未反応単量体の回収を行わないか、あ
るいは、全く回収しないことによって、このような内容
物が回収されるブローダウンタンク中では短時間に多量
の未反応塩化ビニル系単量体が蒸発することになるが、
通気管４が充分に大きな管径と短い管長を有することに
よって、ブローダウンタンクからガスホルダーへ移動す
る際の流体の流動抵抗が低減化される結果、ブローダウ
ンタンク内での処理圧を１ｋｇ／ｃｍ2Ｇ以下に保つこ
とが可能となるのである。FIGS. 1 and 2 show an example of the recovery equipment of the present invention, and the recovery method of the present invention will be specifically described. However, the present invention is not limited thereto. The device of the present invention
A polymerization reaction tank 1 for producing a vinyl chloride polymer by polymerizing a vinyl chloride monomer or a mixture of a vinyl chloride monomer and a monomer copolymerizable therewith; A transfer pipe 2 for transferring an article, a blowdown tank 3 having a withstand pressure allowable pressure of 1 kg / cm 2 G or less for temporarily storing or passing the content transferred through the transfer pipe 2; A vent pipe 4 provided at the outlet of the blow-down tank 3, a pressure gauge 7 for detecting the pressure in the blow-down tank 3, and a pressure detected by the pressure gauge 7 being equal to or less than a pressure-resistant allowable pressure of the blow-down tank. A pressure regulating valve 6 for regulating the flow rate in the transfer pipe 2 at the inlet of the blowdown tank 3 and a gas holder 5 for holding the gaseous unreacted monomer moving through the ventilation pipe 4. And
Reference numeral 8 denotes a seal pot provided in the middle of the ventilation pipe 4. The seal pot has a function of draining water accumulated in the ventilation pipe 4 and a function of releasing gas when the gas pressure rises abnormally. A pipe 9 is connected to the bottom of the blowdown tank 3 for transferring liquid substances such as vinyl chloride polymer and water from the contents in the blowdown tank to a device for removing vinyl chloride monomer in earnest. The valve 10 is installed. The polymerization reaction tank 1 used in the present invention may be any one that is used for polymerization of a normal vinyl chloride polymer. Further, the transfer pipe 2 used in the present invention may be one used for the production of ordinary vinyl chloride polymers. The allowable pressure resistance of the blowdown tank 3 used in the recovery equipment of the present invention is 1 kg / cm 2 G or less. Further, the capacity is 1 to 3 times the capacity of the polymerization reaction tank, preferably 1.
5 to 2.5 times. Since a high-pressure tank is not required, equipment costs can be reduced. In the present invention, the ventilation pipe 4 connecting the blowdown tank 3 and the gas holder 5 is
It is preferable to have a pipe diameter sufficiently larger than the transfer pipe 2,
1.5 to 4 times the inner diameter of the transfer tube 2, preferably 2 to 3 times,
Dimensionally 200 to 500 mm, preferably 250 to 4
00 mm. Further, the length of the ventilation pipe is preferably short, and is preferably 150 m or less. In the polymerization reaction tank 1, the unreacted monomer is not sufficiently recovered in advance, or is not recovered at all. Unreacted vinyl chloride monomer will evaporate,
When the ventilation pipe 4 has a sufficiently large pipe diameter and a short pipe length, the flow resistance of the fluid when moving from the blowdown tank to the gas holder is reduced. As a result, the processing pressure in the blowdown tank becomes 1 kg /. cm 2 G or less.
【０００７】更に、ブローダウンタンク３に圧力計７を
設置し、この圧力を調整できる調整弁６を移送管に設置
するのが好ましい。これによって、ブローダウンタンク
３内での処理圧がその耐圧許容圧力を越えそうな場合
に、回収量の微調整が可能となり、安定運転に寄与す
る。更に、好ましくは、該調整弁６をブローダウンタン
ク３の直近に設置すれば、該管内で未反応単量体がフラ
ッシュ蒸発することで発生する衝撃で配管が破損しない
よう、係るフラッシュ蒸発を最小限に抑えることが可能
となる。また、図２に示すように、該移送管２をブロー
ダウンタンク３の側面内周に沿って接線方向に沿うよう
に接続すれば、移送管を通って該ブローダウンタンクへ
回収される重合系内容物が一気に吐出される衝撃による
設備の破損の防止に効果的である。Further, it is preferable to install a pressure gauge 7 in the blowdown tank 3 and to install an adjusting valve 6 capable of adjusting the pressure in the transfer pipe. Thus, when the processing pressure in the blowdown tank 3 is likely to exceed the pressure-resistant allowable pressure, the recovery amount can be finely adjusted, which contributes to stable operation. Further, preferably, if the regulating valve 6 is installed in the immediate vicinity of the blowdown tank 3, the flash evaporation is minimized so that the pipes are not damaged by the shock generated by the flash evaporation of the unreacted monomer in the pipe. It is possible to keep it to a minimum. Also, as shown in FIG. 2, if the transfer pipe 2 is connected along the inner periphery of the side surface of the blowdown tank 3 in a tangential direction, the polymerization system recovered to the blowdown tank through the transfer pipe is connected. This is effective in preventing damage to the equipment due to the impact of discharging the contents at a stretch.
【０００８】本発明で使用するガスホルダー５は通常の
塩化ビニル系重合体の回収設備において使用されている
もの、例えば、水槽内に倒立して設けられた水封容器を
用いることができる。通常、その容量はブローダウンタ
ンク３より充分に大きいことが好ましい。As the gas holder 5 used in the present invention, the gas holder used in ordinary vinyl chloride polymer recovery equipment, for example, a water-sealed container installed upside down in a water tank can be used. Usually, it is preferable that the capacity is sufficiently larger than the blowdown tank 3.
【０００９】本発明の回収設備は、塩化ビニル系単量体
を重合反応槽に仕込んで該塩化ビニル単量体の８０重量
％以上を重合させ、重合反応槽内の圧力が１ｋｇ／ｃｍ
2Ｇ以上の時点で回収を開始するのが望ましい。回収開
始時の重合反応槽内の圧力が３ｋｇ／ｃｍ2Ｇ以上であ
るときに本発明の効果は大きく、更に好ましくは５ｋｇ
／ｃｍ2Ｇ以上のときである。回収開始時の重合反応槽
内の圧力が重合の主反応中に示す圧力であるときであっ
ても構わない。また、本発明では、最初に重合反応槽に
仕込んだ塩化ビニル系単量体のうち、重合しなかった未
反応単量体の５０重量％未満を重合反応槽の頂部に設け
られた配管から予め回収する操作を行ったのちに、残り
の全ての内容物をブローダウンタンクへ回収する方法を
採用しても構わない。本発明では、未反応塩化ビニル系
単量体のうちの５０重量％以上が重合反応槽中に存在し
ている段階で、該重合反応槽から内容物を回収し始める
方法を採用するときに、効果は大きく、更に好ましくは
９０重量％以上が存在しているときである。本発明で
は、重合反応槽中で未反応塩化ビニル系単量体を実質的
に回収することなく、該反応槽中の内容物を全部ブロー
ダウンタンクへ回収することも可能であり、本発明の効
果は、この方法を採用するときに最も好ましい。このよ
うに、本発明では、重合反応後に通常行う反応槽内での
未反応単量体の回収操作を削減または全く省略できるた
め、当該重合反応を終了し、次のバッチの重合に移るま
でのタイムラグを有効に短縮することが可能となる。こ
の結果、重合反応槽の実稼働率を高めることができ、塩
化ビニル系重合体の生産効率を向上することに寄与する
のである。また、本発明の回収設備を用いて回収を行え
ば、ブローダウンタンクにおけるタンク内の圧力を低圧
とすることが可能となり、回収される内容物中に含まれ
る未反応単量体の濃度が低く保たれる結果、内容物中に
おける局部的な圧力変動のバラツキが小さくなる。この
ため、次の工程における本格的な未反応塩化ビニル系単
量体の除去工程での負荷量を低減できるとともに、該除
去工程における運転管理が安定化するという優れた効果
を奏するのである。すなわち、ブローダウンタンクの内
容物中の未反応単量体の濃度が高いと、前記の本格的な
未反応塩化ビニル系単量体の除去工程に係る装置の入り
口で、未反応単量体のフラッシュ蒸発の勢いが強いため
に、塩化ビニル系重合体粒子が飛散して該装置の内壁に
付着し、１００℃近い高温にて長時間曝される結果、該
重合体粒子が着色し、のちにこれが剥離して製品粒子中
に混入し製品の品質を低下させる。本発明者らの検討結
果によれば、本発明の回収装置を使用せずに通常行われ
ている設備を用いて、重合反応槽中で未反応単量体の回
収を行わずに内容物を一気にタンクへ回収した場合に
は、前記の本格的な塩化ビニル系単量体の除去工程を経
た後の重合系内容物中における塩化ビニル系単量体の濃
度は最大で５３０ｐｐｍであったが、本発明の装置を使
用して同様に回収を行った場合には、塩化ビニル系単量
体の濃度は１０ｐｐｍ以下で安定していた。In the recovery equipment of the present invention, a vinyl chloride-based monomer is charged into a polymerization reaction tank to polymerize at least 80% by weight of the vinyl chloride monomer, and the pressure in the polymerization reaction tank is 1 kg / cm.
It is desirable to start the collection at 2G or more. The effect of the present invention is great when the pressure in the polymerization reactor at the start of the recovery is 3 kg / cm 2 G or more, and more preferably 5 kg / cm 2 G.
/ Cm 2 G or more. The pressure in the polymerization reaction tank at the start of the recovery may be the pressure shown during the main reaction of polymerization. Also, in the present invention, of the vinyl chloride monomers initially charged in the polymerization reaction tank, less than 50% by weight of the unreacted monomer that has not been polymerized is previously removed from a pipe provided at the top of the polymerization reaction tank. After performing the collecting operation, a method of collecting all remaining contents into the blowdown tank may be adopted. In the present invention, when employing a method of starting to collect the contents from the polymerization reaction tank at a stage where 50% by weight or more of the unreacted vinyl chloride monomer is present in the polymerization reaction tank, The effect is great, more preferably when more than 90% by weight is present. In the present invention, it is possible to collect all of the contents in the reaction tank to the blowdown tank without substantially collecting the unreacted vinyl chloride-based monomer in the polymerization reaction tank. The effect is most favorable when employing this method. As described above, in the present invention, the operation of recovering unreacted monomers in the reaction vessel usually performed after the polymerization reaction can be reduced or omitted altogether, so that the polymerization reaction is terminated and the process proceeds to the polymerization of the next batch. The time lag can be effectively reduced. As a result, the actual operation rate of the polymerization reactor can be increased, which contributes to improving the production efficiency of the vinyl chloride polymer. Further, by performing recovery using the recovery equipment of the present invention, it is possible to reduce the pressure in the tank in the blowdown tank, the concentration of unreacted monomer contained in the recovered content is low As a result, variations in local pressure fluctuations in the contents are reduced. For this reason, it is possible to reduce the load in the full-scale step of removing the unreacted vinyl chloride-based monomer in the next step, and to achieve an excellent effect of stabilizing the operation control in the removal step. That is, when the concentration of the unreacted monomer in the contents of the blow-down tank is high, the unreacted monomer is removed at the entrance of the apparatus related to the full-scale unreacted vinyl chloride monomer removal step. Because of the strong momentum of flash evaporation, the vinyl chloride polymer particles scatter and adhere to the inner wall of the device, and are exposed for a long time at a high temperature of about 100 ° C. As a result, the polymer particles are colored, This peels off and mixes into the product particles, lowering the quality of the product. According to the study results of the present inventors, using the equipment which is usually used without using the recovery apparatus of the present invention, the contents were recovered without performing the recovery of unreacted monomers in the polymerization reaction tank. When collected in a single tank, the concentration of the vinyl chloride monomer in the polymerization content after the full-scale vinyl chloride monomer removal step was 530 ppm at the maximum, When the same recovery was performed using the apparatus of the present invention, the concentration of the vinyl chloride monomer was stable at 10 ppm or less.
【００１０】[0010]
【実施例】以下に本発明を実施例に基づいて更に詳細に
説明するが、これらは何ら本発明を限定するものではな
い。The present invention will be described in more detail with reference to the following Examples, which do not limit the present invention in any way.
【００１１】実施例１ 共に設計圧力１，０００ｍｍ水中の２，５００ｍ3の容
積を持つガスホルダーと１００ｍ3のブローダウンタン
クがあり、その気相部間が移送管の直径の２．５倍で、
約２５０ｍｍの直径を有する通気管で８０ｍの距離で接
続し、その間に凝縮水を抜き出すシールポットを有して
いる。重合反応槽の容積は６０ｍ3で、その移送管はポ
ンプ及びＰＩＣ（ブローダウンタンク圧力調整弁）を経
由してブローダウンタンクに接続している。尚、この接
続部はブローダウンタンクの側面内周に対して接線方向
に接続している。この装置を用いて、重合温度５７℃に
て、塩化ビニル単量体仕込量２０，０００ｋｇ、水仕込
量２４，０００ｋｇ、分散剤として部分ケン化ポリビニ
ルアルコールを塩化ビニル単量体に対して４４０ｐｐ
ｍ、重合開始剤としてｔ−ブチルパーオキシデカネート
３００ｐｐｍとクミルパーオキシネオデカノエート２０
０ｐｐｍを添加して重合を行い、重合反応槽内の圧力が
５ｋｇ／ｃｍ3Ｇまで低下した時点（塩化ビニル単量体
のうちの９１．８重量％が重合した時点）で内容物を前
記移送管を経由して前記ブローダウンタンクへ回収し
た。この時ブローダウンタンク内の圧力は３００ｍｍ水
柱以下でコントロールされた。このとき、重合工程所要
時間は５４５分、収率は９１．８％、生産性は２６Ｔ／
ｍ3・Ｍであった（重合器の容積１ｍ3並びに３０日当た
りに生産できる塩化ビニル重合体の量トン数）。Example 1 A gas holder having a capacity of 2,500 m 3 in water with a design pressure of 1,000 mm and a blow-down tank of 100 m 3 were provided, and the space between the gas phase portions was 2.5 times the diameter of the transfer pipe. ,
It is connected at a distance of 80 m by a vent pipe having a diameter of about 250 mm, and has a seal pot for draining condensed water between them. The volume of the polymerization reactor is 60 m 3 , and the transfer pipe is connected to the blowdown tank via a pump and a PIC (blowdown tank pressure regulating valve). Note that this connection portion is connected tangentially to the inner periphery of the side surface of the blowdown tank. Using this apparatus, at a polymerization temperature of 57 ° C., a charged amount of vinyl chloride monomer was 20,000 kg, a charged amount of water was 24,000 kg, and partially saponified polyvinyl alcohol was used as a dispersant at 440 pp with respect to the vinyl chloride monomer.
m, 300 ppm of t-butyl peroxydecanoate and cumyl peroxy neodecanoate 20 as a polymerization initiator
The polymerization was carried out by adding 0 ppm, and the content was transferred when the pressure in the polymerization reactor dropped to 5 kg / cm 3 G (when 91.8% by weight of the vinyl chloride monomer was polymerized). It was collected in the blowdown tank via a tube. At this time, the pressure in the blowdown tank was controlled at a water column of 300 mm or less. At this time, the polymerization step required time was 545 minutes, the yield was 91.8%, and the productivity was 26 T /
m 3 · M (1 m 3 of polymerization vessel volume and tonnage of vinyl chloride polymer that can be produced per 30 days).
【００１２】実施例２ 重合反応槽内の圧力が６．５ｋｇ／ｃｍ3Ｇまで低下し
た時点で重合反応槽内において未反応単量体のみを回収
し、更に重合反応槽内の圧力が５ｋｇ／ｃｍ3Ｇに低下
した時点（塩化ビニル系単量体のうちの９１．２重量％
が重合した時点）で重合系内容物をブローダウンタンク
に回収した以外は、実施例１に準じて実施した。重合反
応槽内で回収した塩化ビニル系単量体の量は、反応槽内
の圧力が６．５ｋｇ／ｃｍ3Ｇのときに該反応槽内に存
在していた未反応塩化ビニル系単量体に対して５０重量
％より少ない量であった。回収中のブローダウンタンク
内の圧力は３００ｍｍ水柱以下でコントロールされた。
重合工程所要時間は５１０分、で収率９１．２％であり
２８．２Ｔ／ｍ3・Ｍの生産性であった。Example 2 When the pressure in the polymerization reactor dropped to 6.5 kg / cm 3 G, only the unreacted monomer was recovered in the polymerization reactor, and the pressure in the polymerization reactor was further reduced to 5 kg / cm 3. cm 3 G (91.2% by weight of the vinyl chloride monomer)
At the time of polymerization), except that the polymerization content was collected in a blowdown tank. The amount of the vinyl chloride monomer recovered in the polymerization reaction tank is determined by the amount of the unreacted vinyl chloride monomer existing in the reaction tank when the pressure in the reaction tank is 6.5 kg / cm 3 G. Less than 50% by weight. The pressure in the blowdown tank during collection was controlled at a water column of 300 mm or less.
The time required for the polymerization step was 510 minutes, the yield was 91.2%, and the productivity was 28.2 T / m 3 · M.
【００１３】実施例３ 重合反応槽内の圧力が６．５ｋｇ／ｃｍ3Ｇに低下した
時点（塩化ビニル系単量体のうちの９０．４重量％が重
合した時点）で重合系内容物をブローダウンタンクに回
収した以外は、実施例１に準じて実施した。この時もブ
ローダウンタンクの圧力は３００ｍｍ水柱以下でコント
ロールされた。重合工程所要時間は４３７分で収率は９
０．４％、生産性は３２．８Ｔ／ｍ3・Ｍであった。Example 3 When the pressure in the polymerization reaction tank dropped to 6.5 kg / cm 3 G (when 90.4% by weight of the vinyl chloride monomer was polymerized), the polymerization content was removed. The procedure was performed in the same manner as in Example 1 except that the gas was collected in the blowdown tank. At this time, the pressure of the blowdown tank was controlled at a water column of 300 mm or less. The polymerization time is 437 minutes and the yield is 9
The productivity was 0.4% and the productivity was 32.8 T / m 3 · M.
【００１４】本発明は高い重合生産性と安価な建設費を
兼ね備えた回収装置であり、この装置を使用して重合系
内容物の回収を行うことによって、引き続き行われる本
格的な塩化ビニル系単量体の除去工程における運転が安
定化するとともに、塩化ビニル系樹脂製品中における塩
化ビニル系単量体の残留濃度が低い値で安定化し、製品
の品質の向上にも寄与するものである。The present invention is a recovery apparatus having both high polymerization productivity and low construction cost. By recovering polymerization contents using this apparatus, it is possible to carry out full-scale vinyl chloride-based single-unit operation. In addition to stabilizing the operation in the monomer removal step, the residual concentration of the vinyl chloride-based monomer in the vinyl chloride-based resin product is stabilized at a low value, thereby contributing to the improvement of product quality.
【図１】塩化ビニル系重合体回収設備Fig. 1 Vinyl chloride polymer recovery equipment
【図２】ブローダウンタンクを上からみた図FIG. 2 is a view of the blowdown tank as viewed from above.
１・・重合反応槽、 ２・・移送管、 ３・・ブローダ
ウンタンク、４・・通気管、 ５・・ガスホルダ
ー、 ６・・・調整弁、７・・圧力計、 ８・・
シールポット1. Polymerization reaction tank, 2. Transfer pipe, 3. Blowdown tank, 4. Ventilation pipe, 5. Gas holder, 6. Regulator valve, 7, Pressure gauge, 8.
Seal pot
Claims (7)
ルとこれと共重合可能な単量体との混合物を重合して塩
化ビニル系重合体を製造するための重合反応槽と、
（ｂ）該反応槽から重合反応後の塩化ビニル系重合体と
未反応単量体を含む内容物を移送するための移送管と、
（ｃ）該移送管を経て移送される前記内容物を一時的に
貯留または通過させるためのタンクであって、その内容
積が前記重合反応槽の内容積の１〜３倍であり、耐圧許
容圧力が１ｋｇ／ｃｍ2Ｇ以下であるブローダウンタン
クと、（ｄ）該ブローダウンタンク出口に設けられた通
気管と、（ｅ）前記ブローダウンタンク内の圧力が前記
耐圧許容圧力以下になるようにブローダウンタンク入り
口の移送管内の流量を調整する圧力調整手段と、（ｆ）
該通気管を経て移動してくる未反応単量体を含むガスを
保留するためのガスホルダーとを有し、前記通気管の内
径が前記移送管の内径より大きいことを特徴とする、塩
化ビニル重合設備における未反応単量体の回収装置。1. A polymerization reactor for producing a vinyl chloride polymer by polymerizing (a) a vinyl chloride monomer or a mixture of vinyl chloride and a monomer copolymerizable therewith,
(B) a transfer tube for transferring the content containing the vinyl chloride polymer and the unreacted monomer after the polymerization reaction from the reaction tank;
(C) a tank for temporarily storing or passing the contents transferred through the transfer pipe, the inner volume of which is 1 to 3 times the inner volume of the polymerization reaction tank; A blow-down tank having a pressure of 1 kg / cm 2 G or less; (d) a ventilation pipe provided at the outlet of the blow-down tank; and (e) a pressure in the blow-down tank being equal to or less than the pressure-resistant allowable pressure. Pressure adjusting means for adjusting the flow rate in the transfer pipe at the inlet of the blowdown tank;
A gas holder for retaining gas containing unreacted monomers moving through the vent pipe, wherein the inner diameter of the vent pipe is larger than the inner diameter of the transfer pipe, An unreacted monomer recovery unit in the polymerization facility.
１．５〜４倍である請求項１記載の回収装置。2. The recovery device according to claim 1, wherein the inner diameter of the ventilation pipe is 1.5 to 4 times the inner diameter of the transfer pipe.
り、重合反応槽から該ブローダウンタンクへ接続する移
送管が、該ブローダウンタンクの側面内周に対してその
接線方向に沿うように接続されていることを特徴とする
請求項１または２記載の回収装置。3. The blow-down tank has a circular inner peripheral surface, and a transfer pipe connected from the polymerization reaction tank to the blow-down tank is tangential to the inner peripheral surface of the blow-down tank. The recovery device according to claim 1 or 2, wherein the recovery device is connected.
体とこれと共重合可能な単量体との混合物を反応槽に仕
込んで該単量体の８０重量％以上を重合させた後、未反
応単量体の内５０重量％以上が残存している状態で該残
存する未反応単量体と塩化ビニル系重合体を含む反応槽
の内容物をブローダウンタンクへ回収し、該ブローダウ
ンタンク内の圧力を１ｋｇ／ｃｍ2Ｇ以下に保ちつつ、
該ブローダウンタンクから前記未反応単量体を含むガス
をガスホルダーへ回収することを特徴とする、塩化ビニ
ル重合設備における未反応単量体の回収方法。4. A vinyl chloride monomer or a mixture of a vinyl chloride monomer and a monomer copolymerizable with the vinyl chloride monomer is charged into a reaction vessel, and 80% by weight or more of the monomer is polymerized. In a state where 50% by weight or more of the unreacted monomer remains, the contents of the reaction vessel containing the remaining unreacted monomer and vinyl chloride polymer are collected in a blowdown tank, While keeping the pressure in the down tank at 1 kg / cm 2 G or less,
A method for recovering unreacted monomers in a vinyl chloride polymerization facility, comprising recovering a gas containing the unreacted monomers from the blowdown tank to a gas holder.
ている状態で、該残存する未反応単量体と塩化ビニル系
重合体を含む内容物をブローダウンタンクへ回収するこ
とを特徴とする請求項４記載の回収方法。5. A method in which 90% by weight or more of the unreacted monomer remains, and the remaining content containing the unreacted monomer and the vinyl chloride polymer is collected in a blowdown tank. The recovery method according to claim 4, characterized in that:
のときに、該反応槽の内容物を前記ブローダウンタンク
へ回収することを特徴とする請求項４記載の回収方法。6. The method according to claim 4, wherein when the internal pressure of the polymerization reactor is 3 kg / cm 2 G or more, the contents of the reactor are recovered to the blowdown tank.
のときに、該反応槽中の内容物をブローダウンタンクへ
回収することを特徴とする請求項４記載の回収方法。7. The method according to claim 4, wherein when the internal pressure of the polymerization reactor is 5 kg / cm 2 G or more, the contents in the reactor are recovered to a blowdown tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27651697A JP3972427B2 (en) | 1996-09-25 | 1997-09-24 | Apparatus and method for recovering unreacted monomer in vinyl chloride polymerization facility |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8-274048 | 1996-09-25 | ||
| JP27404896 | 1996-09-25 | ||
| JP27651697A JP3972427B2 (en) | 1996-09-25 | 1997-09-24 | Apparatus and method for recovering unreacted monomer in vinyl chloride polymerization facility |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10152522A true JPH10152522A (en) | 1998-06-09 |
| JP3972427B2 JP3972427B2 (en) | 2007-09-05 |
Family
ID=26550876
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27651697A Expired - Lifetime JP3972427B2 (en) | 1996-09-25 | 1997-09-24 | Apparatus and method for recovering unreacted monomer in vinyl chloride polymerization facility |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3972427B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114452921A (en) * | 2021-12-27 | 2022-05-10 | 昆明云能化工有限公司 | Production system of polyvinyl chloride resin for cables |
-
1997
- 1997-09-24 JP JP27651697A patent/JP3972427B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114452921A (en) * | 2021-12-27 | 2022-05-10 | 昆明云能化工有限公司 | Production system of polyvinyl chloride resin for cables |
| CN114452921B (en) * | 2021-12-27 | 2024-04-30 | 昆明云能化工有限公司 | Production system of polyvinyl chloride resin for cables |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3972427B2 (en) | 2007-09-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101493531B1 (en) | An apparatus for the production of polyethylene and ethylene copolymers | |
| EP0801081B1 (en) | Method of drying solid polymer and drying apparatus | |
| EP3077423B1 (en) | Process for separating components of a reaction mixture obtained by high-pressure polymerization of ethylenically unsaturated monomers | |
| US9637569B2 (en) | Vessel for separating components of a reaction mixture obtained by high-pressure polymerization of ethylenically unsaturated monomers with integrated bursting discs | |
| EA020150B1 (en) | Process for recycling product streams separated from a hydrocarbon-containing feed stream | |
| US20080058481A1 (en) | Transfer Vessel Between Flash Tank and Purge Column | |
| US7098301B1 (en) | High pressure filter method of separating polymer solids and unreacted monomer | |
| JPH10152522A (en) | Apparatus for recovering unreacted monomer in vinyl chloride polymerization facility and recovery therefor | |
| BG100383A (en) | Method of polymerization of olefins in a gas phase | |
| CN114746169B (en) | High pressure polymerization system and high pressure polymerization process for polymerization of ethylenically unsaturated monomers | |
| US2956995A (en) | Continuous process for the production of aliphatic monoolefin polymers | |
| JPH0345726B2 (en) | ||
| US3562227A (en) | Process for separating polymerization solvent media from elastomeric polymer | |
| GB2028836A (en) | Method for Recovery of Unreacted Vinyl Chloride Monomer from an Aqueous Polymerizate Slurry | |
| JPH0351723B2 (en) | ||
| CN111848838B (en) | Method and apparatus for devolatilizing polymers | |
| KR100311553B1 (en) | Recovery device and recovery method of unreacted monomer in vinyl chloride polymerization device | |
| US2999560A (en) | Separation for flare systems | |
| US4128516A (en) | Process for the gentle degasification of coagulation-sensitive PVC latices | |
| EP3898708B1 (en) | High-pressure polymerization process of ethylenically unsaturated monomers in a polymerization reactor | |
| EP0452748B1 (en) | Process for polymerizing a monomer | |
| JPS62104815A (en) | Suspension polymerization of fluoroethylene and apparatus therefor | |
| CA1203348A (en) | Separation of polymer from hydrocarbon solvent in a process for the manufacture of polymers of ethylene | |
| JPH11152301A (en) | High-pressure polymerizer for ethylenic polymer and preparation of ethylenic polymer using it | |
| JPH05310814A (en) | Method of recovering vinyl monomer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20040823 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20060816 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20060822 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20061010 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20070417 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20070419 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20070522 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20070604 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100622 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100622 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110622 Year of fee payment: 4 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110622 Year of fee payment: 4 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313113 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110622 Year of fee payment: 4 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110622 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120622 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120622 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130622 Year of fee payment: 6 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| EXPY | Cancellation because of completion of term |